Master/Slave designation is determined by jumpers on IDE drives. Most drives have adequate markings on them to identify these jumper positions. If not marked clearly, you will need the manufacturer's data to determine that designation.
If you are curious about a working system just power-up in set-up mode (usually by depressing (f1-or-f2) during boot-up sequence, your system-bios will display this information for you.
Some IDE drives have a master/slave jumper, but a significant number of IDE drives defaulted to a "cable select" setting where the drive would determine for itself whether it was the master or the slave by which of the two sockets on the cable it was plugged into.
Master and slave does not apply to scsi drives
We generally use the jumpers to set the disk drives as master or slave.
the hard drive should be set to master...
There are jumpers on the drive itself that can be configured to set it up as a master or a slave. Refer to your hard drive's documentation for the pins to use for these configurations.
master if the ide cable has a single drive connection. if the ide cable has the master and slave connection. then set the drive to master with slave.
Each IDE slot can handle two drives. One drive will be the master and the other will be the slave depending o the configuration. If the jumpers of one drive is configured to set the drive as MA (Master), the second must be configured to SL (Slave). Both drives may be configured as CS (Cable Select), if so, The positioning on the ribbon cable will determine whic one is the master and which is the slave
master if the ide cable has a single drive connection. if the ide cable has the master and slave connection. then set the drive to master with slave.
The Harddrive needs to be set as "master" and the CD ROM as Slave.
first Hard drive is Master and additional will be set to slave.
That would depend on certain variables, such as whether you were putting it on the same cable as the other drive. In IDE, you must have a Master drive on each channel. The second drive must be set to Slave. You were not clear in which drive you could not change the jumper. Assuming the drive in the computer is alone on the cable, it is set to Master, so your new drive must be either set to Slave and be placed on the same cable, or set as Master and placed on another cable.
SATA and IDE are operated on different buses, with different controllers. A SATA drive is not considered a "master" or a "slave"; it has a channel all to itself. If the IDE drive is by itself on the controller, it should be set as Master.